We would like to share some testimonials from some of our customers that helped give our Silicone Sippy Spouts a 4.0 star rating on Amazon. You can find this review and others like that at our Goglass Amazon Store.
I bought these for a wide mouth stainless steel bottle I already had for my daughter. I didn't want to buy a whole new stainless sippy cup, so I hunted for a wide mouth sippy spout. These were the only ones I found. The bottle brand is The Safe Starter and this spout fits it perfectly. I'm really glad I can continue using a perfectly good vessel past the bottle stage.
The spout works with just suction, and also with pressure. So it works for a younger baby that only knows to use suction, and it supplies more liquid when pressure is applied by an older child that knows how to.